This invention pertains to systems for transferring ammunition for weapons, and more specifically, it pertains to an ammunition cradle for a weapon mounted on a rotatable carriage.
Ships have been used as weapons platforms for centuries. In modem times, warships mounting major caliber guns are often used for heavy bombardment of targets on shore. The emphasis on design of warships in the past has often focused on mounting a relatively large number of guns on a single platform due to the high cost involved with building large ships capable of supporting even one major caliber gun. It was possible for such a ship to maintain a high rate of fire overall due to the large number of weapons.
Warships of today are often used to support limited engagements in which it is necessary for the weapons to have pinpoint accuracy in order to minimize collateral damage to non-military targets, and to provide close fire support for troops on the ground. Due to the relatively high cost of weapons with the desired degree of accuracy, it is desirable to develop weapons with a high rate of fire so as to minimize the need for large numbers of weapons on a single platform.
Ammunition rounds for major caliber weapons normally comprise a projectile, a propellant charge and a primer or other igniting means. Separate ammunition is a term that refers to systems in which the three components are separately provided and are combined at the weapon. The term semi-fixed ammunition refers to systems in which the primer and the propellant are packaged together, and the term fixed ammunition refers to systems in which all three components are packaged together. Ammunition rounds for major caliber guns are typically of the separate or semi-fixed ammunition type. For the purposes of this application, the term ammunition round is used interchangeably to refer to complete ammunition rounds as well as any separate portion thereof.
Guns are usually mounted in turrets or carriages on a warship, and the barrel of the gun is generally controllable in elevation as well as in azimuth, which is referred to as train. The term elevation axis refers to the axis about which the gun rotates in elevation, and the term train axis refers to the axis about which the gun rotates in azimuth. Ammunition rounds are normally supplied to the gun carriages from magazines located deep in the hull through one or more ammunition handling systems. Such ammunition handling systems are well known. Examples of previous ammunition handling systems are described in U.S. Pat. No. 3,218,930 to Girouard, et al., U.S. Pat. No. 3,122,967 to Johnson, et al., U.S. Pat. No. 4,457,209 to Scheurich, et al., and U.S. Pat. No. 4,481,862 to Wiethoff, et al., each of which is hereby fully incorporated herein by reference.
Historically, loading of major caliber guns, particularly in a warship has been accomplished by either an xe2x80x9con-axisxe2x80x9d or an xe2x80x9coff-axisxe2x80x9d loading method. In the on-axis method, a gun cradle mounted so as to pivot about the elevation axis of the gun is aligned with a vertical ammunition hoist disposed along the train axis of the gun to allow a single ammunition round to be transferred to the cradle. The cradle is then pivoted upward into alignment with the barrel so that the ammunition round may be rammed into the breech and barrel to be fired. Such xe2x80x9con-axisxe2x80x9d systems offer the advantage of a simple mechanism and loading motion. A disadvantage of standard on-axis loading systems, however, is that only one hoist and cradle may be used per barrel, thus limiting the Firing rate of the gun. Moreover, if semi-fixed or separate ammunition is used, the ammunition components must be loaded into the ammunition hoist in sequential fashion, and more than one pivoting cycle of the cradle may be necessary to transfer the multiple components of a single round to the breech of the gun for firing.
Another method of loading is known as xe2x80x9coff-axis loadingxe2x80x9d, meaning that the ammunition rounds arc supplied vertically to a pivoting cradle from a hoist located along an axis offset from the train axis of the gun. A carrier and various mechanisms are used to horizontally translate the ammunition round and orient it for alignment with the barrel.
Off-axis loading is desirable in that it allows a system to use multiple hoists and multiple gun cradles, thereby improving the rate of fire from that achievable with an on-axis loading system. Since the azimuth of the gun breech and cradle varies with the azimuth of the gun in an off-axis loading system, however, a complex mechanism is required to receive the ammunition round from the off-axis hoist, transfer it the distance from the hoist to the cradle of the gun, and align it with the breech so it can be loaded into the gun. The necessity to xe2x80x9cfollowxe2x80x9d the train motion of the gun makes the firing rate of the gun dependant on the azimuth of the gun, and thus can cause a significant negative impact on the rate of fire at certain azimuth angles. Moreover, the modem tendency is toward increased use of precision guided munitions in major caliber weapons. Known off-axis ammunition handling systems are not well suited to handle the increased length of these longer ammunition rounds.
What is needed is an ammunition handling system for loading a weapon that enables a uniform, rapid rate of fire and that is suited to handling ammunition rounds of increased length.
The present invention is a multiple cell ammunition cradle for a weapon that enables a uniform, rapid rate of fire, independent of the relative azimuthal orientation of the weapon, and that is suited to handling ammunition rounds of increased length. In a preferred embodiment, the invention includes a cradle having a rotor with a plurality of cells formed therein. The cradle is pivotable about the elevation axis of the weapon, and may be disposed in a charging position and a loading position. When in the charging position, each of the cells is controllably, selectively alignable, by means of the rotor, with an ammunition hoist to receive an ammunition round or component in each cell. When the cradle is pivoted into the loading position, the rotor may be positioned so that each of the cells is alignable with the breech and barrel of the weapon so that the ammunition round or component may be loaded into the weapon and fired. The present invention could also be used for handling and disposing of a spent cartridge case.
The ammunition cradle of the present invention is suitable for handling any type of ammunition including separate, semi-fixed, or fixed ammunition, and may also be used to handle rocket propelled or precision guided munitions, which may be of increased length relative to a standard major caliber round. It is anticipated that the present invention may provide the benefits of reduced gun system size, and complexity through the elimination of the complex mechanisms used in prior art systems. It is anticipated that the ammunition cradle, when used with a weapon, may enable firing rates of ten rounds per minute and above.
Thus, the invention may be characterized in one embodiment as a multiple cell ammunition cradle system for a weapon having a carriage and a barrel. The system comprises at least one ammunition hoist and a cradle operably coupled to the carriage. The cradle is selectively positionable in a charging position and a loading position. The cradle has a carrier, which may be a rotor with a plurality of cells, each cell adapted to receive a component of an ammunition round. The rotor is rotatable about a rotor axis, and is controllably positionable so that each cell is selectively alignable with the ammunition hoist when the cradle is positioned in the charging position and so that each cell is selectively alignable with the barrel when the cradle is positioned in the loading position.
The invention may also be characterized as a method for sequentially loading and firing a weapon having a barrel disposed along a loading axis, the weapon being mounted on a carriage. The method comprises the steps of: providing an ammunition transfer system comprising a plurality of ammunition hoists and a cradle operably coupled to the carriage, the cradle having a rotor with a plurality of cells adapted to receive an ammunition component, the rotor being controllably positionable so that each cell is selectively alignable with the ammunition hoists to receive the ammunition component and selectively alignable with the barrel to load the ammunition component into the gun; loading an ammunition component into each of the plurality of cells from the ammunition hoists; positioning the cradle so that the cradle is disposed along the loading axis; rotating and positioning the rotor so that one of the plurality of cells is axially aligned with the barrel; and ramming the ammunition component from the aligned cell into the barrel.
The invention may also be characterized as a weapon and ammunition loading system. The weapon and system has a carriage, a barrel mounted on the carriage, at least one ammunition hoist for supplying ammunition components, and a cradle having a carrier with a plurality of cells. The cradle is controllably positionable in a charging position and a loading position. The carrier may be arranged so that each cell is alignable with the ammunition hoist for receiving the ammunition component when the cradle is in the charging position and alignable with the barrel for transferring the ammunition component for loading into the weapon when the cradle is in the loading position.
Additional objects, advantages, and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.